The Hamiltonian System Of Unmanned Boats Stabilizes And Tracks Control

Over the past decades,unmanned marine surface vehicles（USV）have been widely deployed for various missions such as marine monitoring,hydrographic surveying and charting,mineral resources exploitation,scientific research,military field.It is attracting more and more attention from researcher all over the world.The perfect motion control performance is the basic premise for the completion of USV’s different missions,so the motion control system is one of basic research contents of USVs.Due to the USVs also needing to perform various tasks,it is very important and necessary to improve the endurance of USVs.However,it has become a factor limiting the ability to improve the endurance due to the banlance between speed,wave resistance and payload during the design process.Thereforce,how to design a motion controller not only guarantee the dynamical performance but also optimize energy loss become a problem that should be urgently investigated.The unmanned marine surface vehicles systems can be viewed as signal and energy transformation devices with multi-port,upon signal and energy transformation,add up their signals and energies to determine control behavior of the full system.The energy control of unmanned marine surface vehicles is by the energy conversion analysis of the system that is used to judge the operating state of system.The energy control approach also optimize the input energy,output energy and loss energy of the USV.It has impor-tant theoretical significance and practical use value to study the motion control design of unmanned marine surface vehicles systems from the viewpoint of energy.The main research work of this paper is as following:（1）Motion control problem of USV is discussed based on the port-controlled Hamil-tonian model of USV.Based on the standerd ship’s six-degree-freedom（DOF）motion model,we obtain a simplified USV’s three-degree-freedom motion model.Then we have further discussed the effects of nonlinear damping and environmental disturbances and uncertainty.Using the port-controlled Hamiltonian theory,the simplified 3-DOF model of USV is transformed to the port-controlled Hamiltonian model.Then the char-acteristics of model such as dissipation,passivity and energy balance are analyzed.Mo-tion control system of USV is a passive system.（2）In the study of speed and heading control problem of USV,a hybrid coordination control strategy based on signal and energy method is proposed.The energy controller uses the Port-Controlled Hamiltonian（PCH）control approach,and the signal controller uses the Lyapunov’s direct method and backstepping approach.The design of coordina-tion control strategy is used to adjust the strength of the signal controller and energy controller.Simulation results confirm the validity and stability of control algorithm,and the results show that the proposed algorithm can quickly track signals with energy optimization.（3）In terms of USV’s stabilization control problem,based on energy shaping princi-ple we designed the stabilization controller for USV systems.We use a port-Hamiltonian framework to design a novel nonlinear set-point-regulation controller with integral ac-tion.Stability analysis shows that the proposed controller can guarantee the closed-loop system’s stability.The simulation results shows the effective of the proposed approach.（4）In terms of USV’s trajectory Tracking control problem,an energy-based trajce-tory tracking robust controller is proposed.Firstly,a disturbance observer is constructed to estimate the unkown time-varying enviromental disturbance.Then,a trajectory track-ing controller is proposed based on energy shaping and damping injection control prin-ciple and the disturbance observer.The closed-loop system is asymptotically stable by theoretical analysis.To cope with the problem that the disturbances estimator is not easy to construct in practical applications,we proposed a novel trajectory track-ing controller based on state error PCH principle and L₂gain disturbance attenuation approach.Simulation results are given to illustrate the effectiveness of the approach.（5）In terms of USV’s path Following control problem,we present a energy based adaptive path-following controller.The proposed algorithm is motivated by a line-of-sight（LOS）guidance principle.The desired heading angle is obtained by the adaptive LOS navigation algorithm,then it is used as the expected input of the energy-based speed and heading controller.The path following problem of USV is solved.The closed-loop system is asymptotically stable by theroetical analysis.The simulation re-sults show that the proposed controller can quickly track the desired path,while the closed system has the lowest energy consumption.The effectiveness of the proposed controller is verified by theoretical analysis and simulation.Based on energy-sharping control principle,this paper has in-depth discussions con-cerning the heading and speed control problem,the point stablization control problem,trajectory tracking control problem and path following control problem of USV with considering the external distrubances effects and model uncertainties.It’s provied a new approach to the design of motion control system for USVs,and the proposed ap-proach will optimize the energy loss problem of USVs.